diff --git a/src/main/java/com/peanut/modules/common/controller/ClassController.java b/src/main/java/com/peanut/modules/common/controller/ClassController.java
index c40f44c2..004d91ae 100644
--- a/src/main/java/com/peanut/modules/common/controller/ClassController.java
+++ b/src/main/java/com/peanut/modules/common/controller/ClassController.java
@@ -462,12 +462,14 @@ public class ClassController {
             if (userCertificateList.size() > 0){
                 UserCertificate u0 = userCertificateList.get(0);
                 String certificateNo = u0.getCertificateNo();
-                int no = Integer.parseInt(certificateNo.substring(certificateNo.indexOf("1")+1,certificateNo.indexOf("1")+7))+1;
                 if ("A".equals(type)){
+                    int no = Integer.parseInt(certificateNo.substring(4,10))+1;
                     res = "NO."+String.format("%06d", no);
                 }else if ("B".equals(type)){
+                    int no = Integer.parseInt(certificateNo.substring(4,10))+1;
                     res = "NO."+String.format("%06d", no);
                 }else if ("ZK".equals(type)){
+                    int no = Integer.parseInt(certificateNo.substring(6,12))+1;
                     res = "NO.ZK"+String.format("%06d", no);
                 }
             }else {